Concrete admixture additive

ABSTRACT

A new family of concrete admixture additives can be derived from reacting a mixture of olefins/cyclic olefins-maleic anhydride copolymers and methoxy polyethylene glycol amines and/or polyethylene glycol monoalkyl ethers, or a mixture of styrene-maleic anhydride copolymers and methoxy polyethylene glycol amines and/or polyethylene glycol monoalkyl ethers, or a mixture of styrene-olefins/cyclic olefins-maleic anhydride terpolymers and methoxy polyethylene glycol amines and/or polyethylene glycol monoalkyl ethers. These reactions lead to formation of a kind of carboxylic salt containing polymer, which can be used alone in concrete. Only a small amount of this substance is needed to provide excellent water reduction, high concrete flowability and high early strength.

This application is a Divisional of Application Ser. No. 10/655,343filed on Sep. 4, 2003 now U.S. Pat. No. 7,312,291, and for whichpriority is claimed under 35 U.S.C. §120; the entire contents of whichis hereby incorporated by reference.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a concrete admixture additive for waterreduction and to the process of making the same.

(b) Description of the Related Art

In a typical concrete mixing process, a large amount of water is addedto increase flowability of the concrete. However, water overdose lowersconcrete compression strength and adversely affects other properties.While on the contrary, lack of water causes concrete slump anddeterioration, which is harmful to a construction process. Many chemicaladditives have been invented in the past to improve concrete flowabilitywithout the need of increasing the amount of water.

Traditional concrete water reducers are formed by mixing lignin as maincomponent with naphthalene sulfonic acid sodium salt. Although the costof such kind of additives is relatively low, they cannot providedesirable concrete water reduction when the effective content in theconcrete is low. For example, when a type F water reducer, whichconsists mainly of naphthalene-based compounds, is used, rapid concreteslump will result.

Recently copolymers of acrylic acid or maleic anhydride and alkenylethers and their derivatives have been found to improve concreteadmixture flowability. [Japanese Patent Publication (Kokai) Nos285140/88 and 163108/90]. Besides, copolymers of maleic acid and itssalt and ester derivatives and hydroxy-terminated allyl ether andcopolymers of maleic acid and partially esterified styrene are known toenhance concrete admixture flowability [U.S. Pat. Nos. 4,471,100 and5,158,996]. Such chemical reagents are classified as carboxylic typeadditives. But those concrete additives still can not provide all therequired properties. For example, although esterified acrylic acidcopolymers provide good concrete admixture flowability, they alsoprolong the hardening time.

In view of the above, a new family of concrete admixture additives isdisclosed and claimed in the present invention. These additives, even ata relatively low additive level, can provide improved water reduction,increase concrete flowability, reduce concrete slump and enhancecompression strength. In addition, the processes of making such concreteadmixture additives are also disclosed and claimed.

BRIEF SUMMARY OF THE INVENTION

The objective of the present invention is to provide a chemical additivethat can be blended into concrete admixture to increase the flowability,reduce the slump and enhance the compression strength of the concreteadmixture without needing additional water in the concrete admixture.

A concrete admixture additive of the invention was derived from reactinga mixture of olefins/cyclic olefins-maleic anhydride copolymers andmethoxy polyethylene glycol amines and/or polyethylene glycol monoalkylethers, or a mixture of styrene-maleic anhydride copolymers and methoxypolyethylene glycol amines and/or polyethylene glycol monoalkyl ethers,or a mixture of styrene-olefins/cyclic olefins-maleic anhydrideterpolymers and methoxy polyethylene glycol amines and/or polyethyleneglycol monoalkyl ethers. These reactions lead to the formation of a kindof carboxylic salt containing polymer, which can be used alone asadditive in concrete admixture. Only a small amount of this substance isneeded to provide excellent water reduction, high concrete flowabilityand high early strength. Due to these properties, the additive is veryuseful in providing more options of construction method.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the water reduction for the concreteadmixture additive of the present invention as compared to a prior artwater reducer over a range of additive level.

FIG. 2 is a diagram showing the concrete slump for the concreteadmixture additive of the present invention as compared to a prior artwater reducer as a function of time.

DETAILED DESCRIPTION OF THE INVENTION

The concrete admixture additive in the present invention is a type ofglycol amine-glycol ether derivatives of olefins/cyclic olefins-maleicanhydride copolymers, or glycol amine-glycol ether derivatives ofstyrene-maleic anhydride copolymers, or glycol amine-glycol etherderivatives of styrene-olefins/cyclic olefins-maleic anhydrideterpolymers.

The aforementioned polymers react with a certain amount of methoxypolyethylene glycol amine or polyethylene glycol monoalkyl ether, or amixture of the two, followed by an acidation step, to producecarboxylated polymers. Then, alkaline reagents containing alkaline metalcations, alkaline earth metal cations or ammonium are used to convertthe carboxylated polymers to ionic polymers which have the chemicalformula:

wherein

R¹ is hydrogen or methyl;

R² is hydrogen or methyl;

X is selected from the group consisting of C₆-C₁₀ aromatic group, C₆-C₁₀sulfonated aromatic group, C₅-C₆ cyclic alkyl group and C₁₋₁₀ alkoxygroup;

Y is selected from the group consisting of C₂-C₅ saturated aliphaticgroup, C₂-C₅ unsaturated aliphatic group,

(wherein R⁵ and R⁶ are respectively selected from the group consistingof hydrogen, halogen, C₁₋₁₀ alkyl group, C₆₋₁₀ aromatic group, C₆₋₁₀fluoroaromatic group, C₁₋₁₀ alkoxy group, C₂₋₁₀ alkenyl group, C₇₋₁₁aromatic alkyl group, C₈₋₁₂ aromatic alkenyl group and C₇₋₁₁ alkylaromatic group); and

R³ and R⁴ are respectively NHR⁷, OR⁷, OH or O⁻M⁺ (wherein M⁺ is alkalinemetal cation, alkaline earth metal cation or ammonium, R⁷ is anoxyalkenyl or polyoxyalkenyl having the formula (ZO)_(p)R⁸ where Z is aC₂-C₅ aliphatic group, p can be any integer from 5 to 100 and R⁸ is aC₁-C₅ aliphatic group or C₆-C₁₀ aromatic group); and

l, m and n indicate molar ratios for different repeating units in thepolymer composition, wherein (the letter) l is an integer from 0 to 25,m is an integer from 0 to 25, and n is an integer from 0 to 50, providedat least two of l, m and n are not zero. The preferred value for (theletter) l is from 0 to 10, for m from 0 to 10, and for n from 0 to 25.The more preferred value for (the letter) l is from 0 to 5, for m from 0to 5, and for n from 0 to 25.

In the formula of the above chemical additive for concrete admixture,the preferred R¹ and R² is hydrogen.

In the formula of the above chemical additive for concrete admixture,the preferred X is phenyl or sulfonated phenyl.

In the formula of the above chemical additive for concrete admixture,

a preferred Y is—CH₂—CH₂—;

another preferred Y is —CH₂—CH═CH—CH₂—,

-   -   or

-   -   or a mixture of both;

another preferred Y is —CH₂—CH═CH—CH₂—,

-   -   or

-   -   or a mixture of both;

another preferred Y is

and still another preferred Y is

The preparation and synthesis method for the above high performancechemical additives for concrete admixture is as follows: adding thereagents in the following from the first to the fourth in order,conducting mixing and reaction at 20 ˜180° C. to obtain the targetproducts. The chemical compounds involved in the reaction are asfollows:

(1) The first reagent contains 1˜75% by weight of polymers with theformula:

wherein

R¹¹ is hydrogen or methyl;

R¹² is hydrogen or methyl;

X′ is selected from the group consisting of C₆-C₁₀ aromatic group,C₆-C₁₀ sulfonated aromatic group, C₅-C₆ cyclic alkyl group, and C₁₋₁₀alkoxy group;

Y′ is selected from the group consisting of C₂-C₅ saturated aliphaticgroup, C₂-C₅ unsaturated aliphatic group,

(wherein R¹⁵ and R¹⁶ are respectively selected from the group consistingof hydrogen, halogen, C₁₋₁₀ alkyl group, C₆₋₁₀ aromatic group, C₆₋₁₀fluoroaromatic group, C₁₋₁₀ alkoxy group, C₂₋₁₀ alkenyl group, C₇₋₁₁aromatic alkyl group, C₈₋₁₂ aromatic alkenyl group and C₇₋₁₁ alkylaromatic group); and

r, s and t indicate the molar ratios for respective repeating units inthe polymer structure, wherein r is an integer from 0 to 25, s is aninteger from 0 to 25, and t is an integer from 0 to 50, provided atleast two of r, s and t are not zero. The preferred value for r is from0 to 10, for s from 0 to 10, and for t from 0 to 25. The more preferredvalue for r is from 0 to 5, for s from 0 to 5, and for t from 0 to 25.

(2) The second reagent contains 1˜75% by weight of oxyalkene orpolyoxyalkene, having the formula H₂N(Z′O)_(q)R¹⁸ or HO(Z′O)_(q)R¹⁸,wherein Z′ is a C₂-C₅ aliphatic group, q is an integer from 5 to 100,and R¹⁸ is a C₁-C₅ aliphatic group or C₆-C₁₀ aromatic group.

(3) The third reagent contains 1˜10% by weight of inorganic H₂SO₄, HCl,HNO₃, BF₃, SnC₁₂ or sulfonic organic acids such as CH₃SO₃H, C₂H₅SO₃H,C₄H₉SO₃H, CCl₃SO₃H, benzene sulfonic acid, p-xylene sulfonic acid, oro-xylene sulfonic acid.

(4) The fourth reagent contains 1˜10% by weight of alkaline reagentsrepresented by the formula M(OR¹⁹)_(v), wherein M is alkaline metal likeNa or K, or alkaline earth metal like Mg or Ca, or ammonium NH₄, v isthe valence of M, and R¹⁹ is selected from the group consisting ofhydrogen, C₁₋₁₀ alkyl group, C₆₋₁₀ aromatic group, C₁₋₁₀ alkoxy group,C₇₋₁₁ aromatic alkyl group, C₈₋₁₂ aromatic alkenyl group and C₇₋₁₁ alkylaromatic group.

In the formula of the above chemical additive for concrete admixture,the preferred R¹¹ and R¹² is hydrogen.

In the formula of the above chemical additive for concrete admixture, apreferred X′ is phenyl or sulfonated phenyl.

In the formula of the above chemical additive for concrete admixture,

a preferred Y′ is —CH₂—CH₂—;

another preferred Y′ is—CH₂—CH═CH—CH₂—,

-   -   or

-   -   or a mixture of both;

another preferred Y′ is —CH₂—CH═CH—CH₂—,

or

or a mixture of both;

another preferred Y′ is

and still another preferred Y′ is

The following examples are given to illustrate the reactions practicedin some of the embodiments of the present invention for manufacturingthe concrete admixture additive.

EXAMPLE 1

Put 5 units of norbornene, 25 units of maleic anhydride and 0.5 unit ofAIBN in a reaction flask. Add 200 mL of benzene as solvent. Agitate themixture for 10 minutes, followed by slow heating. Let the mixture reactat 80° C. for 2 hours. After filtration, a white solid compound can beobtained. This product is a copolymer of norbornene and maleicanhydride, with average molecular weight of 4500.

EXAMPLE 2

Put 2.5 units of norbornene, 2.5 units of styrene, 25 units of maleicanhydride and 0.5 unit of AIBN in a reaction flask. Add 300 mL ofbenzene as solvent. Agitate the mixture for 10 minutes, followed by slowheating. Let the mixture react at 80° C. for 3 hours. After filtration,a white solid compound can be obtained. This product is a terpolymer ofnorbornene, styrene and maleic anhydride, with average molecular weightof 5600.

EXAMPLE 3

Put 26.5 units of styrene-maleic anhydride copolymer (3:10 molar ratio,average molecular weight 3800; Sartomer SMA® EF-30) in 100 units ofisopropanol. Add 21.2 units of methoxy polyethylene glycol amine(EO:PO=32:10, average molecular weight 2000, Huntsman Jeffamine®M-2070). Heat the solution up to 90° C. Conduct the reaction underagitation for 5 hours. Add 1 M sulfuric acid and continue the reactionfor 4 hours. Finally, neutralize the solution by 1N NaOH_(aq). Theproduct obtained is a brown, viscous liquid (Polymer E1).

By using the procedures in the example, we can obtain a series of glycolamine derivatives of styrene-maleic anhydride copolymer in differentmolar ratios by reacting it with methoxy polyethylene glycol amine withaverage molecular weight of 2000. The derivatives are in a viscousliquid state.

EXAMPLE 4

Put 26.5 units of styrene-maleic anhydride copolymer (3:10 molar ratio,average molecular weight 3800; Sartomer SMA® EF-30) in 100 units ofisopropanol. Add 21.2 units of polyethylene glycol monomethyl ether(EO:PO=3:2, average molecular weight 750). Heat the solution up to 110°C. Conduct the reaction under agitation for 5 hours. Add 1M sulfuricacid and continue the reaction for 4 hours. Finally, neutralize thesolution by 1N Ca (OH)_(2aq). The product obtained is a brown, viscousliquid (Polymer E2).

By using the procedures in the example, we can obtain a series of glycolether derivatives of styrene-maleic anhydride copolymer in differentmolar ratios by reacting it with polyethylene glycol monomethyl etherwith average molecular weight of 750. The derivatives are in a viscousliquid state.

EXAMPLE 5

Put 26.5 units of styrene-maleic anhydride copolymer (3:10 molar ratio,average molecular weight 3800, Sartomer SMA® EF-30) in 100 units ofisopropanol. Add 10.5 units of methoxy polyethylene glycol amine(EO:PO=32:10, average molecular weight 2000, Huntsman Jeffamine®M-2070). Add 10.7 units of polyethylene glycol monomethyl ether(EO:PO=3:2, average molecular weight 750). Heat the solution up to 90°C. Conduct the reaction under agitation for 5 hours. Raise thetemperature to 110° C. and conduct the reaction for 2 hours. Add 1Msulfuric acid solutions and continue the reaction for 4 hours. Finally,neutralize the solution by 1N NaOH_(aq). The product obtained is abrown, viscous liquid (Polymer E3).

By using the procedures in the example, we can obtain a series of glycolamine-glycol ether derivatives of styrene-maleic anhydride copolymer indifferent molar ratios by reacting it with methoxy polyethylene glycolamine with average molecular weight of 2000 and polyethylene glycolmonomethyl ether with average molecular weight of 750. The derivativesare in a viscous liquid state.

EXAMPLE 6

Put 26.5 units of norbornene-maleic anhydride copolymer (1:5 molarratio, average molecular weight of 4500, obtained from Example 1) in 100units of isopropanol. Add 21.2 units of methoxy polyethylene glycolamine (EO:PO=32:10, average molecular weight of 2000, HuntsmanJeffamine® M-2070). Heat the solution up to 90° C. Conduct the reactionunder agitation for 5 hours. Add 1M sulfuric acid solutions and continuethe reaction for 4 hours. Finally, neutralize the solution by 1N Ca(OH)₂ solution. The product obtained is a brown, viscous liquid (PolymerE4).

By using the procedures in the example, we can obtain a series of glycolamine derivatives of norbornene-maleic anhydride copolymer in differentmolar ratios by reacting it with methoxy polyethylene glycol amine withaverage molecular weight of 2000. The derivatives are in a viscousliquid state.

EXAMPLE 7

Put 26.5 units of norbornene-maleic anhydride copolymer (1:5 molarratio, average molecular weight of 4500, obtained from Example 1) in 100units of isopropanol. Add 21.2 units of polyethylene glycol monomethylether (EO:PO=3:2, average molecular weight of 750). Heat the solution upto 110° C. Conduct the reaction under agitation for 5 hours. Add 1Msulfuric acid solutions and continue the reaction for 4 hours. Finally,neutralize the solution by 1N Ca (OH)₂ solution. The product obtained isa brown, viscous liquid (Polymer E5).

By using the procedures in the example, we can obtain a series of glycolether derivatives of norbornene-maleic anhydride copolymer in differentmolar ratios by reacting it with polyethylene glycol monomethyl etherwith average molecular weight of 750. The derivatives are in a viscousliquid state.

EXAMPLE 8

Put 26.5 units of norbornene-maleic anhydride copolymer (1:5 molarratio, average molecular weight of 4500, obtained from Example 1) in 100units of isopropanol. Add 10.5 units of methoxy polyethylene glycolamine (EO:PO=32:10, average molecular weight of 2000, HuntsmanJeffamine® M-2070). Add 10.7 units of polyethylene glycol monomethylether (EO:PO=3:2, average molecular weight of 750). Heat the solution upto 90° C. Conduct the reaction under agitation for 5 hours. Raise thetemperature to 110° C. and continue the reaction for 2 hours. Add 1Msulfuric acid solutions and continue the reaction for 4 hours. Finally,neutralize the solution by 1N Ca (OH)₂ solution. The product obtained isa brown, viscous liquid (Polymer E6).

By using the procedures in the example, we can obtain a series of glycolamine-glycol ether derivatives of norbornene-maleic anhydride copolymerin different molar ratios by reacting it with methoxy polyethyleneglycol amine with average molecular weight of 2000 and polyethyleneglycol monomethyl ether with average molecular weight of 750. Thederivatives are in a viscous liquid state.

EXAMPLE 9

Put 26.5 units of norbornene-styrene-maleic anhydride terpolymers(1:1:10 molar ratio, average molecular weight of 5600, obtained fromExample 2) in 100 units of isopropanol. Add 21.2 units of methoxypolyethylene glycol amine (EO:PO=32:10, average molecular weight of2000, Huntsman Jeffamine® M-2070). Heat the solution up to 90° C.Conduct the reaction under agitation for 5 hours. Add 1M sulfuric acidsolutions and continue the reaction for 4 hours. Finally, neutralize thesolution by 1N Ca (OH)₂ solution. The product obtained is a brown,viscous liquid (Polymer E7).

By using the procedures in the example, we can obtain a series of glycolamine derivatives of norbornene-styrene-maleic anhydride terpolymers indifferent molar ratios by reacting it with methoxy polyethylene glycolamine with average molecular weight of 2000. The derivatives are in aviscous liquid state.

EXAMPLE 10

Put 26.5 units of norbornene-styrene-maleic anhydride terpolymer (1:1:10molar ratio, average molecular weight of 5600, obtained from Example 2)in 100 units of isopropanol. Add 21.2 units of polyethylene glycolmonomethyl ether (EO:PO=3:2, average molecular weight of 750). Heat thesolution up to 110° C. Conduct the reaction under agitation for 5 hours.Add 1M sulfuric acid solutions and continue the reaction for 4 hours.Finally, neutralize the solution by 1N Ca (OH)₂ solution. The productobtained is a brown, viscous liquid (Polymer E8).

By using the procedures in the example, we can obtain a series of glycolether derivatives of norbornene-styrene-maleic anhydride terpolymers indifferent molar ratios by reacting it with polyethylene glycolmonomethyl ether with average molecular weight of 750. The derivativesare in a viscous liquid state.

EXAMPLE 11

Put 26.5 units of norbornene-styrene-maleic anhydride terpolymers(1:1:10 molar ratio, average molecular weight of 5600, obtained fromExample 2) in 100 units of isopropanol. Add 10.5 units of methoxypolyethylene glycol amine (EO:PO=32:10, average molecular weight of2000, Huntsman Jeffamine® M-2070). Add 10.7 units of polyethylene glycolmonomethyl ether (EO:PO=3:2, average molecular weight of 750). Heat thesolution up to 90° C. Conduct the reaction under agitation for 5 hours.Raise the temperature to 110° C. and continue the reaction for 2 hours.Add 1M sulfuric acid solutions and continue the reaction for 4 hours.Finally, neutralize the solution by 1N Ca (OH)₂ solution. The productobtained is a brown, viscous liquid (Polymer E9).

By using the procedures in the example, we can obtain a series of glycolamine-glycol ether derivatives of norbornene-styrene-maleic anhydrideterpolymers in different molar ratios by reacting it with methoxypolyethylene glycol amine with average molecular weight of 2000 andpolyethylene glycol monomethyl ether with average molecular weight of750. The derivatives are in a viscous liquid state.

EXAMPLE 12

Put 26.5 units of butadiene-maleic anhydride copolymers (TotalAcid=12˜14 wt %, average molecular weight of 3100, Sartomer Ricon®130MA-13) in 100 units of isopropanol. Add 21.2 units of methoxypolyethylene glycol amine (EO:PO=32:10, average molecular weight of2000, Huntsman Jeffamine® M-2070). Heat the solution up to 90° C.Conduct the reaction under agitation for 5 hours. Add 1M sulfuric acidsolutions and continue the reaction for 4 hours. Finally, neutralize thesolution by 1N Ca (OH)₂ solution. The product obtained is a brown,viscous liquid (Polymer E10).

By using the procedures in the example, we can obtain a series of glycolamine derivatives of butadiene-maleic anhydride copolymer in differentmolar ratios by reacting it with methoxy polyethylene glycol amine withaverage molecular weight of 2000. The derivatives are in a viscousliquid state.

EXAMPLE 13

Put 26.5 units of butadiene-maleic anhydride copolymers (TotalAcid=12˜14 wt %, average molecular weight of 3100, Sartomer Ricon®130MA-13) in 100 units of isopropanol. Add 21.2 units of polyethyleneglycol monomethyl ether (EO:PO=3:2, average molecular weight of 750).Heat the solution up to 110° C. Conduct the reaction under agitation for5 hours. Add 1M sulfuric acid solutions and continue the reaction for 4hours. Finally, neutralize the solution by 1N Ca (OH)₂ solution. Theproduct obtained is a brown, viscous liquid (Polymer E11).

By using the procedures in the example, we can obtain a series of glycolether derivatives of butadiene-maleic anhydride copolymer in differentmolar ratios by reacting it with polyethylene glycol monomethyl etherwith average molecular weight of 750. The derivatives are in a viscousliquid state.

EXAMPLE 14

Put 26.5 units of butadiene-maleic anhydride copolymers (TotalAcid=19˜21 wt %, average molecular weight of 7500, Sartomer Ricon®130MA-20) in 100 units of isopropanol. Add 10.5 units of methoxypolyethylene glycol amine (EO:PO=32:10, average molecular weight of2000, Huntsman Jeffamine® M-2070). Add 10.7 units of polyethylene glycolmonomethyl ether (EO:PO=3:2, average molecular weight of 750). Heat thesolution up to 90° C. Conduct the reaction under agitation for 5 hours.Raise the temperature to 110° C. and continue the reaction for 2 hours.Add 1M sulfuric acid solution and continue the reaction for 4 hours.Finally, neutralize the solution by 1N Ca (OH)₂ solution. The productobtained is a brown, viscous liquid (Polymer E12).

By using the procedures in the example, we can obtain a series of glycolamine-glycol ether derivatives of butadiene-maleic anhydride copolymerin different molar ratios by reacting it with methoxy polyethyleneglycol amine with average molecular weight of 2000 and polyethyleneglycol monomethyl ether with molecular weight of 750. The derivativesare in a viscous liquid state.

EXAMPLE 15

Put 26.5 units of butadiene-maleic anhydride copolymers (TotalAcid=19˜21 wt %, average molecular weight of 7500, Sartomer Ricon®131MA-20) in 100 units of isopropanol. Add 21.2 units of methoxypolyethylene glycol amine (EO:PO=32:10, average molecular weight of2000, Huntsman Jeffamine® M-2070). Heat the solution up to 90° C.Conduct the reaction under agitation for 5 hours. Add 1M sulfuric acidsolutions and continue the reaction for 4 hours. Finally, neutralize thesolution by 1N Ca (OH)₂ solution. The product obtained is a brown,viscous liquid (Polymer E13).

By using the procedures in the example, we can obtain a series of glycolamine derivatives of butadiene-maleic anhydride copolymer in differentmolar ratios by reacting it with methoxy polyethylene glycol amine withaverage molecular weight of 2000. The derivatives are in a viscousliquid state.

Comparison of Water Reduction and Slump

To compare the water reduction and slump performance of the concreteadmixture additive of the present invention with a prior art waterreducer, two additives are prepared. First, use the carboxylated polymerprepared in Example 5 to prepare a water reducer with 15% solid content.The solution can be blended into a mixture of cement and water to makeconcrete admixture. Then a powdery naphthalene sulfonic acid waterreducer with 92% solid content to mix with water and cement to prepareconcrete admixture. Both water reducers were prepared and tested at thesame additive contents by weight.

The water reduction tests were conducted according to the ASTM C494standard test method, which specifies 307 kg/m³ cement usage and 210kg/m³ water usage in the control group. The mixing was performedaccording to the ASTM C192 standard test method, which specifiesagitator-mixing operation for 3 minutes, stop for 3 minutes, andoperation for 2 minutes.

The results of the water reduction tests were summarized in TABLE 1 andFIG. 1. It can be seen from TABLE 1 that the concrete admixture additiveof the present invention provides excellent water reduction even at lowadditive content.

It can also be seen from FIG. 1 that the carboxylic acid water reducerof the present invention provides higher water reduction than thetraditional naphthalene sulfonic acid water reducer. When water reduceris used at more than 1%, naphthalene sulfonic acid water reducer haspoor water reduction along with bleeding and serious retardedcoagulation.

TABLE 1 Carboxylic Water acid type Cement Water Fine coarse reducerWater (kg/m³) (kg/m³) (kg/m³) (kg/m³) (kg/m³) reduction Plain 307 210837 930 0 0 No. 1 307 191 906 985 0.92(0.3%) 10% No. 2 307 187 919 9961.23(0.4%) 12% No. 3 307 183 921 1000 1.56(0.5%) 14% No. 4 307 179 9241005 1.84(0.6%) 16% No. 5 307 174 932 1014 2.14(0.7%) 17% No. 6 307 168935 1017 3.07(1.0%) 20%

Similarly, it can be seen from TABLE 2 and FIG. 2 that the naphthalenesulfonic acid water reducer causes more serious slump than thecarboxylic acid water reducer of the present invention.

The slump and compression strength as a function of time were summarizedin TABLE 2 for the additive of the present invention and for thenaphthalene sulfonic acid water reducer.

TABLE 2 Slump (cm) Compression strength (psi) 0 30 60 1 7 14 28 Additivetype min min min day day day day Polycarboxylic 19 17 15 492 2791 39975432 Acid Naphthalene 17 14 10 521 2731 3966 5374

From the above test results, we conclude that the chemical additive forconcrete admixture of the present invention provides excellent waterreduction, high concrete flowability, good slump performance, highcompression strength and early hardening strength, as compared to theprior art water reducer.

1. A process for manufacturing a concrete admixture additive, comprisingthe steps of: (a) preparing a first reagent containing 1-75% by weightof a polymer having the formula:

wherein R¹¹ is hydrogen or methyl; R¹² is hydrogen or methyl; X′ isselected from the group consisting of C₆-C₁₀ aromatic group, C₆-C₁₀sulfonated aromatic group, C₅-C₆ cyclic aromatic group, and C₁₋₁₀ alkoxygroup; Y′ is selected from the group consisting of C₂-C₅ saturatedaliphatic group, C₂-C₅ unsaturated aliphatic group,

wherein R¹⁵ and R¹⁶ are respectively selected from the group consistingof hydrogen, halogen, C₁₋₁₀ alkyl group, C₆₋₁₀ aromatic group, C₆₋₁₀fluoroaromatic group, C₁₋₁₀ alkoxy group, C₂₋₁₀ alkenyl group, C₇₋₁₁aromatic alkyl group, C₈₋₁₂ aromatic alkenyl group and C₇₋₁₁ alkylaromatic group; r is an integer from 0 to 25; s is an integer from 0 to25; and t is an integer from 0 to 50; provided at least two of r, s andt are not zero; (b) reacting the first reagent with a second reagent ata temperature between 20 and 180° C., wherein the second reagentcontains 1-75% by weight of at least one oxyalkene or polyoxyalkenehaving the formula H₂N(Z′O)_(q)R¹⁸ or HO(Z′O)_(q)R¹⁸, wherein Z′ is aC₂-C₅ aliphatic group; q is an integer from 5 and 100; and R¹⁸ is aC₁-C₅ aliphatic group or C₆-C₁₀ aromatic group; (c) reacting theresultant mixture of (b) with an acidic reagent to form a carboxylatedpolymeric product, wherein the acidic reagent contains 1-10% by weightof an inorganic acid or sulfuric organic acid; and (d) treating thecarboxylated polymeric product with an alkaline reagent, wherein thealkaline reagent contains 1-10% by weight of a compound having theformula M(OR¹⁹)_(v), wherein M is an alkaline metal cation, alkalineearth metal cation, or ammonium; v is the valence of M; and R¹⁹ isselected from the group consisting of hydrogen, C₁₋₁₀ alkyl group, C₆₋₁₀aromatic group, C₁₋₁₀ alkoxy group, C₇₋₁₁ aromatic alkyl group, C₈₋₁₂aromatic alkenyl group and C₇₋₁₁ alkyl aromatic group.
 2. The processfor manufacturing a concrete admixture additive according to claim 1,wherein r is an integer from 0 to 10; s is an integer from 0 to 10; andt is an integer from 0 to
 25. 3. The process for manufacturing aconcrete admixture additive according to claim 1, wherein r is aninteger from 0 to 5; s is an integer from 0 to 5; and t is an integerfrom 0 to
 25. 4. The process for manufacturing a concrete admixtureadditive according to claim 1, wherein R¹¹ is hydrogen.
 5. The processfor manufacturing a concrete admixture additive according to claim 1,wherein R¹² is hydrogen.
 6. The process for manufacturing a concreteadmixture additive according to claim 1, wherein X′ is phenyl.
 7. Theprocess for manufacturing a concrete admixture additive according toclaim 1, wherein X′ is sulfonated phenyl.
 8. The process formanufacturing a concrete admixture additive according to claim 1,wherein Y′ is —CH₂—CH₂—.
 9. The process for manufacturing a concreteadmixture additive according to claim 1, wherein Y′ is —CH₂—CH═CH—CH₂—,or

or a mixture of both.
 10. The process for manufacturing a concreteadmixture additive according to claim 1, wherein Y′ is


11. The process for manufacturing a concrete admixture additiveaccording to claim 1, wherein Y′ is